A method for cleaning copper tubes of a condenser relates to the cleaning of heat transfer pipelines. The method comprises the following steps: the first step, closing an inlet valve and an outlet valve of circulating water after a turbine condenser is shut down; the second step, flushing the copper tubes of the condenser with clean water; the third step, injecting acid chemical cleaning liquor at water side of the condenser for soak cleaning; the fourth step, neutralizing soak solution with sodium hydroxide; the fifth step, flushing the copper tubes of the condenser with clean water; the sixth step, rinsing the copper tubes of the condenser with clean water; and the seventh step, replacing membrane, and commissioning after cleaning. Compared with the original method of cleaning with chemical agents to be added to a circulating water tank, the method is characterized in that chemical cleaning liquor is added to a single turbine condenser, which can help clean fouling off the copper tubes and improve vacuum degree of the turbine while ensuring no corrosion of the copper tubes, and has the advantages of low agent consumption, low cost, low corrosion rate, good cleaning effect and saving cleaning time. The method can be widely applied to cleaning and maintenance of the copper tubes of the condensers in power plants.